Engine starter



Oct. 5 1926. 1,601,763

W. J. MILLER I ENGINE STARTER Filed August 17, 1923 Wm wlLLlAM \LMILLER @ZMJ Fig.4 7

Aw 6W ing at right angles to the startin Patented Oct. 5, 1926.

WILLIAM J". MILLER, OF

COLUMBUS, OHIO, ASSIGNOR OF ONE-HALF TO JULIUS F.

STONE, OF COLUMBUS, OHIO.

ENGINE STARTER.

' Application filed August 17, 1923. Serial No. 657,889.

This invention relates to the type of gas engine starter characterized by a motor driven pinion that is temporarily advanced into driving engagement with a gear on the fly wheel. In such a starter as now commonly marketed the pinion is advanced to operating position by means of a screw, a stop collar at the end of the screw and a spring being employed to sustain the pinion at its driving position. Because in such construction a screw is employed the pinion moves in a definite and fixed course and the thrust load of the starting motor is very great. The parts are consequently liable to breakage and injury thereby occasioning much trouble and expense. Such troubles are especially likely if in the starting operation the engine reverses as by an advanced spark thereby reversing the normal operation of the pinion. When the parts break the pinion sticks in the fly wheel gear and can only be released by rocking the vehicle backward and forward. If in such an event the starting motor shaft is bent it will be necessary to remove that motor from its support before the pinion can be released the screw holding the pinion against the stop collar.

The object of my invention is to provide a construction in which the pinion is not held in its meshed or engaged position except by the ends of cams or their terminal lugs so that as soon as the motor is fired a retracting spring shall draw the pinion out of mesh to its home position. In my construction the pinion is not compelled to follow a definite path as determined by a screw, but is capable of rocking or rotatshaft in its different positions thereon. W en the pinion is in working engagement with the fly wheel gear there is no pressure or sudden thrust of the pinion against a stop in its driving position the pressure being rotary merelyin that position.

The invention is embodied in the example herein shown and described the features of novelty being finally claimed.

In the accompanying drawing- Figure 1 is a side elevation of the invention the pinion being in the home or nondriving position.

Fig. 2 is a partial section on the line II-II Fig. 1 but on a larger scale.

Fig. 3 is a side view showing the pinion in driving position.

Fig. l shows the cam member and pinion separated from each other.

In the views 5 designates the case of an electric motor and 6 the shaft of the motor. Secured on the outer end of the shaft of the motor is a cam member preferably composed of a plurality of similar fingers 7 each having a spiral cam edge 8 terminating in an abutment 9 having its face parallel with the axis of the motor shaft. The driving pinion includes the gear toothed portion at the inner end of a sleeve 10 slidable on the shaft 6 and fingers 11 equal in number to the fingers 7 with bearing-surfaces 12 terminating in stops 13 adapted to be engaged by the abutments 9. The driving pinion is connected with the cam member by means of a spring 14 adapted to draw the former to the latter with the fingers inter-projecting as illustrated in Fig. 1 so that when the shaft 6 is rotated in the operating direction indicated by the arrow, the cam edges 8 act on the bearing surfaces 12 and tend to throw the pinion member toward the motor and into engagement with the gear teeth 15 of the engine fiy wheel 16. But the throw of the pinion thus referred to is stopped or limited by the engagement of the terminal abutments 9 with the stops 13 and the pinion is driven or rotated without end thrust to operate the fly wheel because of such engagement. The form, number and arrangement of the fingers 7 and 11 are such that spaces occur between them when inter-projected and the pinion member is capable of considerable rocking on the shaft 6 in a plane at right angles to said shaft. This capacity to rock permits the teeth of the pinion to find and adapt its easy entrance to the gear teeth of the fly wheel and also its free escape therefrom by the spring 14 when the operation ofthe shaft of the starting motor is stopped, or when the driving pressure of the pinion is relieved.

To provide a yielding connection between the drive shaft 6 and the cam member the base of the cam member is formed as, one head 7 threaded into a case 17 containing a friction clutch. This clutch includes several disks 18 notched to engage a spline 19 in the case 17 and several disks 2O toothed to engage a groove 21 on a flanged sleeve 22 secured by a set screw 22 to the shaft 6. The disks 18 and 20 are alternated with each other and are held in frictional contact together by means of several springs 23 held in pressing position by the threading engages ment of the head 7 with the case 17. The springs 23 will be made as nearly uniform in size and tension as practicalso that uniform tension can be applied to the friction disks by simply adjusting the case or the head and fixing the two together with a set screw at 24. The adjustment of the clutch is made sufficient to take the load of turning the engine over but so that abnormal or reverse strains are provided for.

In operation, therefore, the cam member is turned by the operation of the shaft 6 through the friction clutch. When the cam member is rotated rapidly the pinion is pro jected toward and into engagement with gear teeth of the fly wheel and its motion imparted to the fly wheel to start the motor engine. When the driving effect of the inion ceases the spring withdraws the mem er from engagement with the gear teeth of the fiy Wheel and to the home position, in which the cam members are reinterlocked because of the reversed action of said members.

The forms of the parts can be changed without departing from the invention as claimed.

What I claim is:

A starter mechanism for an internal combustion engine having a fly wheel provided with an annular spur gear, said starter mechanism'including, in combination, a motor having a shaft extending beyond the motor, a cam member composed of a plurality of fingers each having a spiral cam edge terminating in an abutment having its face parallel with the axis of the motor and slipping frictional means connecting said cam member with the outer end of said shaft, a

driving-pinion longitudinally and rotatably movable on said shaft and located between said cam member and the motor, said pinion having formed therewith a cam member including a plurality of fingers each having a spiral cam edge terminating in a stop, said cam edges and stops ada ted to operatively coengage with the cam e ges and abutments respectively of the first mentioned cam member to throw the pinion into mesh with the gear of the fly Wheel and a spring connecting said cam members, said spring normally tending to draw said cam fingers together into interengagin relation.

. ILLIAM J. MILLER. 

